Housing for a window fan



FIG. 1 is a top perspective view of a housing for a window fan showing our new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a side elevation view thereof, the opposite side being a mirror image thereof; and,

FIG. 4 is a top plan view thereof.

The broken line showing of environmental structure is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a housing for a window fan, as shown and described. 